The Holy Prophet (saww) said:
“Surely there exists in the hearts of the Mu’mineen with respect to Imam Husain (as), a heat that never subsides.” [REF: Mustadrak al-Wasail, vol. 10, pg. 318]

-- WORLDLY AFFAIRS ON ASHOORA --

Imam Ali Reza (as) said:
“Whoever avoids attending to his worldly affairs on the tenth of Muharram, Allah will fulfill all the wishes and desires of this world as well as the hereafter. Whoever considers this day to be a day of mourning, sorrow and weeping for himself, Allah the Glorified will make the day of Qiyamah to be a day of rejoicing for him and his eyes will be cooled in Paradise on account of us. And whoever considers the tenth of Muharram to be a day of prosperity and buys something for his house, then Allah will not give him affluence in that thing. And on the day of Qiyamah he will be made to arise along with Yazid, Ubaydullah bin Ziyad and Umar ibn Sa'ad (may Allah's curse be on all of them) and will be thrown into the lowest abyss of hell.” [REF: Nafasul Mahmum]

-- ONE OF THE MANNERS OF PERFORMING AZADARI --

Imam Baqir (as) on peforming Azadari:
"He should mourn over Husain (A.S.), weep for him and instruct the members of the house to weep for him. He should establish the mourning ceremony in the house by exhibiting lamentations and grief over him; the people should meet one another in their homes and offer condolences and consolation to each other over the calamities which befell him." [REF: Kaamil Az-Ziyaraat Pg:175]

-- AZADARI IS WORSHIP --

Imam Sadiq (as) said:
“The breath of the one who is aggrieved upon the injustice and oppression subjected to us, is Tasbeeh (glorification of Allah), and his grief for our affairs is Ibaadat (worship of Allah)” [REF: Amali-Shaikh Mufid Pg:338]

-- AZADARI: SUPERIOR MOST WORSHIP --

Imam Sadiq (as) said:
“Surely above every act of worship, there is another act of worship and the superior most worship is to love us Ahlulbait (as).” [REF: Al-Mahasin Pg: 113]

Since Azadari is the expression of our love towards Ahlulbait (as), it is superior most worship as per the above mentioned hadith.

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قال امام حسنؑ : و لکن لا یوم کیومک یا ابا عبد اللہ

"But there is no day like you day, O'Aba Abdillah."
[Ref: Bihar Al Anwar Vol:45 Hadees:44]

-- Azadari and Sayed Muhammad Ali Kazmi Burujardi --

Truely! the acts of Azadari are not only permitted or recommended but are obligatory....The Act of Zainab-e-Kubra(sa) shedding blood from her forehead is also a proof for acts of azadari.
[Azadari Az Deed Gaahe Marajiyyat Pg:261]